The present invention relates to a method of assembling a working cylinder, in particular a pneumatic brake booster for automotive vehicles, comprising at least a first and a second casing shell which are interconnected during assembly and sealed relative to one another by an elastic seal clamped therebetween, with the first casing shell including a mounting surface for a member to be actuated by the working cylinder, and with a working piston which acts on a push rod supported on the second casing shell remote from the member to be actuated while in the inactive position.
In working cylinders of this type, it is necessary after the assembly of all components to adjust the unit length between the mounting surface and the end of a push rod in the last operation because the tolerances permissible in the manufacture of the individual components may be cumulative in component assembly in such a way that the final unit length is materially above or below the one prescribed. If the unit length resulting after the assembly of the working cylinder were not corrected in the last operation, an inadmissibly large lost travel would ensue between the working cylinder and the member to be actuated.
In a known brake booster, the unit length is corrected in a final separate operation to conform to the prescribed nominal dimension after the final assembly of the two casing shells.
This method of manufacturing a working cylinder, in particular a brake booster, is complicated, time-consuming and expensive.